Particle separation in xanthan gum solutions

  • Di Li
  • Xingchen Shao
  • Joshua B. Bostwick
  • Xiangchun XuanEmail author
Research Paper
Part of the following topical collections:
  1. Particle motion in non-Newtonian microfluidics


Label-free separation of particles by an intrinsic property can be implemented in microfluidic devices through either an externally imposed field or an inherent flow-induced force. Among the latter type of passive techniques, elastic or elasto-inertial lift-based particle separation in non-Newtonian fluids has received a rapidly growing interest in the past decade. However, current demonstrations of particle separation in non-Newtonian fluids have all taken place in viscoelastic polymer or biological solutions. We demonstrate for the first time a continuous sheath-free separation of polystyrene particles in the flow of weakly elastic xanthan gum (XG) solution through a simple straight rectangular microchannel. This separation is fundamentally different from that in the flow of viscoelastic solutions. We explain the observed particle migrations in XG solutions using the competition of a strong wall-directed (because of the strong shear thinning effect) and a small center-directed (because of the weak elasticity effect) lateral force induced by normal stresses in a Poiseuille flow.


Particle separation Lateral migration Lift force Shear thinning Elasticity Microfluidics 



This work was supported in part by Clemson University through a SEED Grant (XX), and by NSF under Grant Number CBET-1750208 (JB).

Supplementary material

10404_2019_2292_MOESM1_ESM.pdf (1.1 mb)
Supplementary material 1 Experimental images for particle motion in the flow of Newtonian and non-Newtonian fluids over a wide range of flow rates (PDF 1150 kb)


  1. Ahn SW, Lee SS, Lee SJ, Kim JM (2015) Microfluidic particle separator utilizing sheathless elasto-inertial focusing. Chem Eng Sci 126:237–243Google Scholar
  2. Amini H, Lee W, Di Carlo D (2014) Inertial microfluidic physics. Lab Chip 14:2739–2761Google Scholar
  3. Asmolov ES (1999) The inertial lift on a spherical particle in a plane Poiseuille flow at large channel Reynolds number. J Fluid Mech 381:63–87zbMATHGoogle Scholar
  4. Aytouna M, Paredes J, Shahidzadeh-Bonn N, Moulinet S, Wagner C, Amarouchene Y, Eggers J, Bonn D (2013) Drop formation in non-Newtonian fluids. Phys Rev Lett 110:034501Google Scholar
  5. Barnes HA, Hutton JF, Walters K (1989) An introduction to rheology. Elsevier, AmsterdamzbMATHGoogle Scholar
  6. Bird RB, Armstrong RC, Hassager O (1987) Dynamics of polymeric liquids, vol 1. Wiley, HobokenGoogle Scholar
  7. D’Avino G, Maffettone PL (2015) Particle dynamics in viscoelastic liquids. J Non-Newton Fluid Mech 215:80–104MathSciNetGoogle Scholar
  8. D’Avino G, Greco F, Maffettone PL (2017) Particle migration due to viscoelasticity of the suspending liquid and its relevance in microfluidic devices. Annu Rev Fluid Mech 49:341–360MathSciNetzbMATHGoogle Scholar
  9. Del Giudice F, Sathish S, D’Avino G, Shen AQ (2017) “From the edge to the center”: viscoelastic migration of particles and cells in a strongly shear-thinning liquid flowing in a microchannel. Anal Chem 89:13146–13159Google Scholar
  10. Dhahir SA, Walters K (1989) On Non-Newtonian flow past a cylinder in a confined flow. J Rheol 33:781–804Google Scholar
  11. Escudier MP, Smith S (1999) Turbulent flow of Newtonian and shear-thinning liquids through a sudden axisymmetric expansion. Exp Fluid 27:427–434Google Scholar
  12. Gossett DR, Weaver WM, Mach AJ, Hur SC, Tse HT, Lee W, Amini H, Di Carlo D (2010) Label-free cell separation and sorting in microfluidic systems. Anal Bioanal Chem 397:3249–3267Google Scholar
  13. Ha B, Park J, Destgeer G, Jung JJ, Sung HJ (2016) Transfer of microparticles across laminar streams from non-Newtonian to Newtonian fluid. Anal Chem 88:4205–4210Google Scholar
  14. Haase AS, Wood JA, Sprakel LM, Lammertink RG (2017) Inelastic non-Newtonian flow over heterogeneously slippery surfaces. Phys Rev E 95:023105Google Scholar
  15. Haward SJ, Jaishankar A, Oliveira MSN, Alves MA, McKinley GH (2013) Extensional flow of hyaluronic acid solutions in an optimized microfluidic cross-slot device. Biomicrofluid 7:044108Google Scholar
  16. Ho BP, Leal LG (1974) Inertial migration of rigid spheres in two-dimensional unidirectional flows. J Fluid Mech 65:365–400zbMATHGoogle Scholar
  17. Huang PY, Joseph DD (2000) Effects of shear thinning on migration of neutrally buoyant particles in pressure driven flow of Newtonian and viscoelastic fluids. J Non-Newton Fluid Mech 90:159–185zbMATHGoogle Scholar
  18. Japper-Jaafar A, Escudier MP, Poole RJ (2010) Laminar, transitional and turbulent annular flow of drag-reducing polymer solutions. J Non-Newton Fluid Mech 165:1357–1372Google Scholar
  19. Kang K, Lee SS, Hyun K, Lee SJ, Kim JM (2013) DNA-based highly tunable particle focuser. Nat Commun 4:2567Google Scholar
  20. Karimi A, Yazdi S, Ardekani AM (2013) Hydrodynamic mechanisms of cell and particle trapping in microfluidics. Biomicrofluid 7:021501Google Scholar
  21. Lapizco-Encinas BH (2019) On the recent developments of insulator-based dielectrophoresis: a review. Electrophoresis 40:358–375Google Scholar
  22. Leal LG (1979) The motion of small particles in non-Newtonian fluids. J Non-Newton Fluid Mech 5:33–78zbMATHGoogle Scholar
  23. Leal LG (1980) Particle motions in a viscous fluid. Annu Rev Fluid Mech 12:435–476MathSciNetzbMATHGoogle Scholar
  24. Lee DJ, Brenner H, Youn JR, Song YS (2013) Multiplex particle focusing via hydrodynamic force in viscoelastic fluids. Sci Rep 3:3258Google Scholar
  25. Leshansky AM, Bransky A, Korin N, Dinnar U (2007) Tunable nonlinear viscoelastic “focusing” in a microfluidic device. Phys Rev Lett 98:234501Google Scholar
  26. Li D, Xuan X (2018) Fluid rheological effects on particle migration in a straight rectangular microchannel. Microfluid Nanofluid 22:49Google Scholar
  27. Li D, Xuan X (2019) The motion of rigid particles in the Poiseuille flow of pseudoplastic fluids through straight rectangular microchannels. Microfluid Nanofluid 23:54Google Scholar
  28. Li G, McKinley GH, Ardekani AM (2015) Dynamics of particle migration in channel flow of viscoelastic fluids. J Fluid Mech 785:486–505MathSciNetzbMATHGoogle Scholar
  29. Li D, Lu X, Song Y, Wang J, Li D, Xuan X (2016a) Sheathless electrokinetic particle separation in a bifurcating microchannel. Biomicrofluid 10:054104Google Scholar
  30. Li D, Lu X, Xuan X (2016b) Viscoelastic separation of particles by size in straight rectangular microchannels: a parametric study for a refined understanding. Anal Chem 88:12303–12309Google Scholar
  31. Li D, Zielinski J, Kozubowski L, Xuan X (2018) Continuous sheath-free separation of drug-treated human fungal pathogen Cryptococcus Neoformans by morphology in biocompatible polymer solutions. Electrophoresis 39:2362–2369Google Scholar
  32. Lim H, Nam J, Shin S (2014) Lateral migration of particles suspended in viscoelastic fluids in a microchannel flow. Microfluid Nanofluid 17:683–692Google Scholar
  33. Lindner A, Bonn D, Meunier J (2000) Viscous fingering in a shear-thinning fluid. Phys Fluid 12:256–261MathSciNetzbMATHGoogle Scholar
  34. Liu C, Hu G (2017) High-throughput particle manipulation based on hydrodynamic effects in microchannels. Micromachines 8:73Google Scholar
  35. Liu C, Hu G, Jiang X, Sun J (2015a) Inertial focusing of spherical particles in rectangular microchannels over a wide range of Reynolds numbers. Lab Chip 15:1168–1177Google Scholar
  36. Liu C, Xue C, Chen X, Shan L, Tian Y, Hu G (2015b) Size-based separation of particles and cells utilizing viscoelastic effects in straight microchannels. Anal Chem 87:6041–6048Google Scholar
  37. Liu C, Ding B, Xue C, Tian Y, Hu G, Sun J (2016) Sheathless focusing and separation of diverse nanoparticles in viscoelastic solutions with minimized shear thinning. Anal Chem 88:12547–12553Google Scholar
  38. Liu C, Guo J, Tian F, Yang N, Yan F, Ding Y, Wei J, Hu G, Nie G, Sun J (2017) Field-free isolation of exosomes from extracellular vesicles by microfluidic viscoelastic flows. ACS Nano 11:6968–6976Google Scholar
  39. Liu C, Zhao J, Tian F, Chang J, Zhang W, Sun J (2019) λ-DNA and aptamer mediated sorting and analysis of extracellular vesicles. J Am Chem Soc 141:3817–3821Google Scholar
  40. Lu X, Xuan X (2015a) Continuous microfluidic particle separation via elasto-inertial pinched flow fractionation. Anal Chem 87:6389–6396Google Scholar
  41. Lu X, Xuan X (2015b) Elasto-inertial pinched flow fractionation for continuous shape-based particle separation. Anal Chem 87:11523–11530Google Scholar
  42. Lu X, Zhu L, Hua RM, Xuan X (2015) Continuous sheath-free separation of particles by shape in viscoelastic fluids. Appl Phys Lett 107:264102Google Scholar
  43. Lu X, Liu C, Hu G, Xuan X (2017) Particle manipulations in non-Newtonian microfluidics: a review. J Colloid Interface Sci 500:182–201Google Scholar
  44. Martel JM, Toner M (2014) Inertial focusing in microfluidics. Annu Rev Biomed Eng 16:371–396Google Scholar
  45. Munaz A, Shiddiky MJA, Nguyen NT (2018) Recent advances and current challenges in magnetophoresis based micro magnetofluidics. Biomicrofluid 12:031501Google Scholar
  46. Nam J, Lim H, Kim D, Jung H, Shin S (2012) Continuous separation of microparticles in a microfluidic channel via the elasto-inertial effect of non-Newtonian fluid. Lab Chip 12:1347–1354Google Scholar
  47. Nam J, Namgung B, Lim CT, Bae JE, Leo HL, Cho KS, Kim S (2015a) Microfluidic device for sheathless particle focusing and separation using a viscoelastic fluid. J Chromatogr A 1406:244–250Google Scholar
  48. Nam J, Tan JK, Khoo BL, Namgung B, Leo HL, Lim CT, Kim S (2015b) Hybrid capillary-inserted microfluidic device for sheathless particle focusing and separation in viscoelastic flow. Biomicrofluid 9:064117Google Scholar
  49. Nam J, Shin Y, Tan JKS, Lim YB, Lim CT, Kim S (2016) High-throughput malaria parasite separation using a viscoelastic fluid for ultrasensitive PCR detection. Lab Chip 16:2086–2092Google Scholar
  50. Nam J, Jang WS, Hong DH, Lim CS (2019) Viscoelastic separation and concentration of fungi from blood for highly sensitive molecular diagnostics. Sci Rep 9:3067Google Scholar
  51. Rodd LE, Scott TP, Boger DV, Cooper-White JJ, McKinley GH (2005) The inertio-elastic planar entry flow of low-viscosity elastic fluids in micro-fabricated geometries. J Non-Newton Fluid Mech 129:1–22Google Scholar
  52. Sajeesh P, Sen AK (2014) Particle separation and sorting in microfluidic devices: a review. Microfluid Nanofluid 17:1–52Google Scholar
  53. Stoecklein D, Di Carlo D (2019) Nonlinear microfluidics. Anal Chem 91:296–314Google Scholar
  54. Tang W, Jiang D, Li Z, Zhu L, Shi J, Yang J, Xiang N (2019) Recent advances in microfluidic cell sorting techniques based on both physical and biochemical principles. Electrophoresis 40:930–954Google Scholar
  55. Tian F, Zhang W, Cai L, Li S, Hu G, Cong Y, Liu C, Li T, Sun J (2017) Microfluidic co-flow of Newtonian and viscoelastic fluids for high-resolution separation of microparticles. Lab Chip 17:3078–3085Google Scholar
  56. Tian F, Cai L, Chang J, Li S, Liu C, Li T, Sun J (2018) Label-free isolation of rare tumor cells from untreated whole blood by interfacial viscoelastic microfluidics. Lab Chip 18:3436–3445Google Scholar
  57. Tian F, Feng Q, Chen Q, Liu C, Li T, Sun J (2019) Manipulation of bio-micro/nanoparticles in non-Newtonian microflows. Microfluid Nanofluid 23:68Google Scholar
  58. Villone MM, D’Avino G, Hulsen MA, Greco F, Maffettone PL (2013) Particle motion in square channel flow of a viscoelastic liquid: migration vs. secondary flows. J Non Newton Fluid Mech 195:1–8Google Scholar
  59. Won D, Kim C (2004) Alignment and aggregation of spherical particles in viscoelastic fluid under shear flow. J Non-Newton Fluid Mech 117:141–146Google Scholar
  60. Wu M, Ozcelik A, Rufo J, Wang Z, Fang R, Huang TJ (2019) Acoustofluidic separation of cells and particles. Microsyst Nanoeng 5:32Google Scholar
  61. Wyatt NB, Liberatore MW (2009) Rheology and viscosity scaling of the polyelectrolyte xanthan gum. J Appl Polymer Sci 114:4076–4084Google Scholar
  62. Yan S, Zhang J, Yuan D, Li W (2017) Hybrid microfluidics combined with active and passive approaches for continuous cell separation. Electrophoresis 38:238–249Google Scholar
  63. Yang S, Kim JY, Lee SJ, Lee SS, Kim JM (2011) Sheathless elasto-inertial particle focusing and continuous separation in a straight rectangular microchannel. Lab Chip 11:266–273Google Scholar
  64. Yang S, Lee SS, Ahn SW, Kang K, Shim W, Lee G, Hyun K, Kim JM (2012) Deformability-selective particle entrainment and separation in a rectangular microchannel using medium viscoelasticity. Soft Matter 8:5011–5019Google Scholar
  65. Yasuda K, Armstrong RC, Cohen RE (1981) Shear flow properties of concentrated solutions of linear and star branched polystyrenes. Rheol Acta 20:163–178Google Scholar
  66. Yuan D, Zhang J, Yan S, Peng G, Zhao Q, Alici G, Du H, Li W (2016a) Investigation of particle lateral migration in sample-sheath flow of viscoelastic fluid and Newtonian fluid. Electrophoresis 37:2147–2155Google Scholar
  67. Yuan D, Zhang J, Sluyter R, Zhao Q, Yan S, Alicia G, Li W (2016b) Continuous plasma extraction under viscoelastic fluid in a straight channel with asymmetrical expansion–contraction cavity arrays. Lab Chip 16:3919–3928Google Scholar
  68. Yuan D, Tan S, Sluyter R, Zhao Q, Yan S, Nguyen NT, Guo J, Zhang J, Li W (2017a) On-chip microparticle and cell washing using coflow of viscoelastic fluid and newtonian fluid. Anal Chem 89:9574–9582Google Scholar
  69. Yuan D, Tan S, Zhao Q, Yan S, Sluyter R, Nguyen NT, Zhang J, Li W (2017b) Sheathless dean-flow-coupled elasto-inertial particle focusing and separation in viscoelastic fluid. RSC Adv 7:3461–3469Google Scholar
  70. Yuan D, Zhao Q, Yan S, Tang SY, Alici G, Zhang J, Li W (2018) Recent progress of particle migration in viscoelastic fluids. Lab Chip 18:551–567Google Scholar
  71. Zhang J, Yan S, Yuan D, Alici G, Nguyen NT, Warkiani ME, Li W (2016) Fundamentals and applications of inertial microfluidics: a review. Lab Chip 16:10–34Google Scholar
  72. Zhou Y, Ma Z, Tayebi M, Ai Y (2019) Submicron particle focusing and exosome sorting by wavy microchannel structures within viscoelastic fluids. Anal Chem 91:4577–4584Google Scholar
  73. Zirnsak MA, Boger DV, Tirtaatmadja V (1999) Steady shear and dynamic rheological properties of xanthan gum solutions in viscous solvents. J Rheol 43:627–650Google Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringClemson UniversityClemsonUSA

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